Dr Bryan Wilson provides evidence to analysis of the UK-Mauritius treaty on the Chagos Archipelago
The Chagos Archipelago is a remote group of islands in the Central Indian Ocean, and – according to Dr Bryan Wilson, “possibly the most important reef wilderness on the planet”. Negotiations between the UK and Mauritius forged an agreement to transfer sovereignty of the territory to Mauritius in May 2025. In June, Dr Wilson contributed to parliament’s analysis of the agreement in his role as Scientific Advisor to the Chagos Conservation Trust and as an expert on the natural environment of the Archipelago.
Image: Bertarelli Foundation
Part of Bryan’s research (supported by the Bertarelli Foundation's Marine Science Program) is studying the world’s rarest coral – the Chagos brain coral – which is perilously close to extinction and only found in these islands. Bryan says:
“It is a refuge for nature and a part of the world that needs protecting for all generations to follow, not least the Chagossian peoples who used to call it home.”
In 2010, the UK declared a 640,000km2 Marine Protected Area (MPA) around the Archipelago – an area which has some of the most biodiverse waters on the planet with over 220 species of coral, 855 species of fish, and 355 species of mollusc, making it a region of global importance.
Mauritius has been developing its own plans for an MPA, outlined in 2024 according to criteria set by the International Union for Conservation of Nature. Part of the Agreement provides that the UK will support and assist Mauritius in the establishment and management of an MPA in the Chagos Archipelago. In his evidence, Dr Wilson said that if Mauritius were to commit to “an ambitious marine protected area and can manage the environment, with the UK and international support, it might well improve on the existing MPA.”
Part of Bryan’s research is studying the world’s rarest coral – the Chagos brain coral – which is only found in these islands
Image: Jon Slayer / Bertarelli Foundation
However, maintaining and enforcing a large MPA is challenging and resource intensive. Monitoring vessels are needed to patrol the waters in order to prevent illegal, unreported or unregulated fishing activities. Dr Wilson said that Mauritius has only two ocean-going vessels and two small aircraft, which do not have a range that allow them to reach the Chagos Archipelago from Mauritius. In consequence, “Mauritius would have an enormous task ahead of it”.
The Agreement does not specify any detail about the support which the UK will provide to Mauritius in establishing the MPA. Dr Wilson outlined a series of measures which could help to secure the conservation of the coral reef and marine environment around the Chagos Archipelago. In particular, he proposed that a portion of the development funding to be provided by the UK should be used for environmental protection projects.
In his evidence, Dr Wilson said:
“It seems that all environmental negotiations have been left until post-signature. This is the first large-scale marine protected area (or MPA) in the world to change sovereignty. It is absolutely essential that we get this right.”
To read more about the UK-Mauritius treaty on the Chagos Archipelago, visit: https://lordslibrary.parliament.uk/uk-mauritius-treaty-on-the-chagos-archipelago/
